Changes in nephritogenic serum galactose-deficient IgA1 in IgA nephropathy following tonsillectomy and steroid therapy

PLoS One. 2014 Feb 21;9(2):e89707. doi: 10.1371/journal.pone.0089707. eCollection 2014.


Background: Recent studies have shown that galactose-deficient IgA1 (GdIgA1) has an important role in the pathogenesis of IgA nephropathy (IgAN). Although emerging data suggest that serum GdIgA1 can be a useful non-invasive IgAN biomarker, the localization of nephritogenic GdIgA1-producing B cells remains unclear. Recent clinical and experimental studies indicate that immune activation tonsillar toll-like receptor (TLR) 9 may be involved in the pathogenesis of IgAN. Here we assessed the possibility of GdIgA1 production in the palatine tonsils in IgAN patients.

Methods: We assessed changes in serum GdIgA1 levels in IgAN patients with clinical remission of hematuria and proteinuria following combined tonsillectomy and steroid pulse therapy. Further, the association between clinical outcome and tonsillar TLR9 expression was evaluated.

Results: Patients (n = 37) were divided into two groups according to therapy response. In one group, serum GdIgA1 levels decreased after tonsillectomy (59%) alone, whereas in the other group most levels only decreased after the addition of steroid pulse therapy to tonsillectomy (41%). The former group showed significantly higher tonsillar TLR9 expression and better improvement in hematuria immediately after tonsillectomy than the latter group.

Conclusions: The present study indicates that the palatine tonsils are probably a major sites of GdIgA1-producing cells. However, in some patients these cells may propagate to other lymphoid organs, which may partially explain the different responses observed to tonsillectomy alone. These findings help to clarify some of the clinical observations in the management of IgAN, and may highlight future directions for research.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cohort Studies
  • Female
  • Galactose / metabolism
  • Glomerulonephritis, IGA / blood*
  • Glomerulonephritis, IGA / drug therapy
  • Glomerulonephritis, IGA / surgery
  • Glucocorticoids / administration & dosage*
  • Glycosylation
  • Hematuria / blood
  • Hematuria / drug therapy
  • Hematuria / surgery
  • Humans
  • Immunoglobulin A / blood*
  • Male
  • Methylprednisolone / administration & dosage*
  • Protein Processing, Post-Translational
  • Tonsillectomy
  • Treatment Outcome


  • Glucocorticoids
  • Immunoglobulin A
  • Galactose
  • Methylprednisolone

Grant support

A part of this study was supported by research funds from Grant-in-Aids for Progressive Renal Disease Research, Research on intractable disease, from the Ministry of Health, Labor and Welfare of Japan, a grant from Strategic Japanese (JST)-Swiss (ETHZ) Cooperative Scientific Program and a grant from the Study Group on IgA Nephropathy in Japan. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.